Apparatus for erecting cartons

ABSTRACT

An apparatus and method for packaging articles of variable height. The articles are stacked and the height measured. A halfslotted container is then cut to size and scored and slotted. The blank is partially erected and the articles placed into the container through an open side. The container is then closed.

United States Patent [72] Inventors BartonK.Sn1ith [50] FieldolSearch.v......N...,...........................93/49,49.1,

Winnetka, III.;

Ralph W. Grofl', Sr., Cherry Hill; James B. Rodman, Sr., Burlington; Henry F.

[56] References Cited UNITED STATES PATENTS 2,887,022 5/1959 Lubersky et al.

Orzechowski, Lindenwold; Joseph S. Hartle, Sr., Moorestown, NJ. [21] AppLNo. 810,886

93/49UX 3,465,652 9/1969 Belletal....................... 93/49 [22] Filed .14 1969 Jan Primary Examiner-Bernard Stickney Division of Ser. No. 605,321. Dec. 28. 1966,

Attorneys-Leslie G. Noller, John M. Crawford, Daniel C.

Block, Patrick D. Coogan and Kenneth W. Vernon v. n a P s m 4 8 C. h An uw 39B 1 9 02:2. ew Mae PMWT de m ng .1 ts as PA ll 53 47 .ll

ABSTRACT: An apparatus and method for packaging articles of variable height. The articles are stacked and the height measured. A half-slotted container is then cut to size and scored and slotted. The blank is partially erected and the arti-, 93/49 cles placed into the container through an open side The con- B3lb 1/26 tainer is then closed.

[54] APPARATUS FOR ERECTING CARTONS 5 Claims, 15 Drawing Figs.

[51] Int Cl Patented March 2, 1971 5 Sheets-Sheet 1 M m N w W m BARTON K. 8/7/7/1 RALPH M GHOH' JAMES B. ROD/MN Hf/YRY r. ORZECHOWS JOSEPH s. HARI'LL' SR pi- W Q AT rwf vs Patented March 2, 1971 3,566,755

5 Sheets-Sheet 8 Patented March 2, 1971 5 Sheets-Sheet 3 Patented March 2,1971 3,566,755

5 Sheets-Sheet 4 APPARATUS FOR ERECTING CARTONS This is a division of Application Ser. No. 605,321, filed Dec. 28, 1966.

This invention relates to an apparatus for forming, filling and enclosing products within containers. More specifically, this invention relates to a method of and apparatus for wrapping products of fixed lengths, fixed widths and varying heights within containers.

In the art of packaging products of fixed length and width and varying heights, it is the practice to form blanks for each size product to be packaged. The blanks are folded along the usual score lines and formed into a tubular configuration by a manufacurers joint with a top and bottom thereof open. They are then knocked down for storage. When they are to be used, they must be set up and telescoped over the product or the product must be placed into the open-ended container. This practice has proved to be unsatisfactory because a machine is required for each step in the assembly of he blanks that packages the product which substantially increases the cost. Moreover, the manufacturer is required to maintain a large inventory of knocked down containers of varying sizes together with an inventory of filler pads for insertion into the filled containers to insure a tight package. Also, normal height variation in so-called standard size products will result in the container selected being slightly too small or too large. Thus, a tight package of the product is not obtained.

The object of this invention is to provide an apparatus for tightly packaging products having fixed width and length and varying heights.

Another object of this invention is to provide an apparatus for sensing the height of a product to be packaged and then wrapping the product with packaging material that is the exact height of the product.

Another object of this invention is to provide an apparatus for wrapping products wherein a half-slotted blank is cut to the exact dimension of height of the product in response to a sensing means that measures the exact height of the product to be packaged.

Another object of this invention is to provide an apparatus for wrapping packaging material around the product to be packaged wherein the packaging material is cut to the exact dimensions of the product.

It has been discovered that products of a fixed length, fixed width and varying height can be tightly fitted into packaging material. This is accomplished by a machine which measures the height of the product which is to be packaged, finishes a partially slotted and scored container blank, partially forms the container blank to fit and receive the product, finish wrapping the container around the product, form a manufacturers joint, close and seal the closure flaps and discharge the package. As the product enters the machine, a sensing plate is brought to bear on the top of the product to measure the height thereof. A half-slotted container blank is then fed from a hopper into a die cutter which slots the container blank, trims it and scores it according to the sensing plates measurement. The resulting regular slotted container blank moves into a folding station where it is folded into a generally U-shape with lower end wall closure flaps folded to 90 and one lower sidewall closure flap folded to 45. Then, the partially formed container is positioned to accept and be wrapped around the product for which it is specifically sized. With wrapping completed, adhesive is applied to form the manufacturers joint. Adhesive is applied to the flaps which are folded as the completed package moves from the assembly station to the take-away conveyor.

These and other objects and advantages will become manifestly clear to those skilled in the art when taken in conjunction with the detailed drawings and description, wherein:

FIG. I is a perspective schematic illustration of the apparatus for the present invention.

FIG. 2 is a top view with parts shown in cross section of the container illustrating the manner in which the container is folded around the product.

FIG. 3 is a view similar to FIG. 2 illustrating the manner in which the glue flap is formed into the manufacturer's joint.

FIG. 4 is a perspective'view of the partial erecting and rotating means with the blank in position to be folded.

FIG. 5 is a perspective view similar to FIG. 4 but illustrating the lower flaps of the blank being folded into position.

FIG. 6 is a perspective view similar to FIG. 4 but illustrating the blank being formed into another position.

FIG. 7 is a perspective view similar to FIG. 6 but illustrating the partial erecting and rotating means rotated with the blank ready to receive the material to be packaged.

FIG. 8 is a perspective view of the container with the product therein illustrating the manner in which the container is wrapped around the product. v

FIG. 9 is a perspective view similar to FIG. 8 but illustrating the manner in which the bottom flaps are closed.

FIG. 10 is a bottom view of the package as it approaches the flap closing means.

FIG. 11 is a bottom view of the package illustrating the manner in which the bottom flaps are closed.

FIG. 12 is a plan view of the half-slotted blank used with the present invention.

FIG. 13 is a plan view of a regular slotted container blank and the products to be packaged therein after the blank has been cut to the exact size of the height of the product to be packaged.

FIG. 14 is a view of a blank similar to FIG. 13 but illustrating a blank of a different height.

FIG. 15 is a view similar to FIG. 14 but illustrating a blank for packaging a product of yet a still different height.

Referring to FIG. 12 of the drawings, a half-slotted blank 40 is illustrated that is usable with the present invention. The blank 40 is provided with a plurality of vertical score lines 98 to provide the blank 40 with sidewalls 93 and end walls 94 and a glue flap 97. A lower horizontal score line 99 is provided in the conventional manner to form lower sidewall closure walls 95 and lower end wall closure flaps 96. Slots 100, coaxial with the vertical score lines 98 are provided in the usual manner to separate the flaps 95 and 96 in the usual manner.

In FIG. 13, a completed regular slotted blank is illustrated for receiving the product 19. As illustrated, the height of the product 19 is indicated at A. As hereinafter set forth, this height A is measured by a sensing means and then the halfslotted container 40 is formed with an upper score line 102 which will provide a distance A between lower horizontal score line 99 and upper horizontal score line 102. Simultaneously with forming the upper scoreline 102, the upper side wall closure flaps 103 and upper end wall closure flaps 104 are formed with slots 101 therebetween. Also, a portion of the glue flap 97 is removed to form a conventional container blank. In FIG. 14, the half-slotted container blank 40 is illustrated as being cut to a size to receive a product 19' of a different height. As illustrated, the height of the product 19' is indicated at B and the distance between lower horizontal score line 99 and upper horizontal score line 102 is the distance B. Since the height of the product 19' is smaller than the height of the product 19 in FIG. 13, additional material D is removed from the upper portion thereof. In FIG. 15, the half-slotted blank 40 is illustrated as being cut to a size C to receive a product 19" having a height C. Since the height of the material 19" is smaller than the product 19', additional material E is removed as waste. The regular slotted container blanks illustrated in FIGS. 13, 14, and 15 are identical with each other except for the height between the lower horizontal score line 99 and upper horizontal score line 102. The size of the halfslotted blank 40 illustrated in FIG. 12 will be selected for the maximum size of product to be packaged. Thus, if there is any variation in size between packages of products 19, the machine for forming the half-slotted blank 40 into a regular slotted blank will automatically compensate therefor as hereinafter set forth.

Referring now to FIG. 1, the wrapping machine 1 includes a in an orderly manner. The product 19 is then passed to a height sensing mechanism 20 which accurately determines the height of the product 19. The sensed stack of product is advanced by means of conveyor 23 to inserter mechanism 26, said inserter mechanism moves the product 19 into the container for wrapping the product 19. The wrapping machine 1 is also provided with a blank slotting and scoring means 31 which forms the half-slotted blank 40 into a regular slotted container blank. Located adjacent the blank slotting and scoring means 31 is a partial erecting and rotating means 41 which includes the container blank folding means 48. As the blank 40 is held in the position as indicated in FIG. 1, the product 19 is loaded into the partially folded blank and then the sidewall 93 thereof is folded around the produce and a manufacturers joint is formed. An ejector mechanism 74 pushes the container which has been wrapped around the product 19 past bottom flap folding means 83 and onto a ramp 89 where the container is then removed to a top closing mechanism which may be positioned in tandem relationship with the ramp 89.

In the illustration of the present invention, the product 19 being packaged is reams of paper that are being stacked five high with two stacks being packaged within one container. However, it is to be understood that other products can be packaged using the present invention. As illustrated in FIG. 1, the feeding conveyor 2 is provided with a belt 3 extending around pulleys 4 and 5, one of which is driven. The feeding conveyor 2 is provided with guides 6 and 7 that are movable across the belt 3 to guide the reams of paper 19 into the proper position. At the exit end of the feeding conveyor 2 are dual tipple conveyors 8 extending around pulleys 9 and 10. The tipple conveyors 8 are movable up and down so as to stack the reams of paper one on top of the other to form a stack as illustrated in FIG. 1. Dual stacking conveyors 11 receive the stacked reams of paper from the tipple conveyors 8 and move the same to another conveyor 14. The stacking conveyors 11 extend around pulleys 12 and 13 in the usual manner.

When sufficient reams of paper have been stacked onto the conveyor 14, they are moved from the stacking position to a position under the height sensing means 20 by a motor means 16. Cylinder 17 having a piston rod 18, a piston, not shown, and a plate constitute a squaring device to ensure the proper advance of the piled stacks of product 19. The sensing means 20 consists of a rod 21 which is mechanically or otherwise actuated to move in a vertical plane. Mounted on the lower end of the rod 21 is a plate 22 which engages the top of the product 19 to be packaged. When the sensing means 20 is actuated, the exact height of the product 19 is accurately measured. This distance is then relayed to the blank slotting and scoring means 31. Accordingly, the height of the container for the particular package underneath the sensing means 20 is exactly determined.

The product 19 is then moved by means of conveyor 23, which is mounted around the pulleys 24 and 25, from the sensing means 20 to the inserter tray which is part of air motor 27 assembly. The inserting means 26 includes a tray over fork arrangement, the tray receiving the product 19 from the sensing means, said tray being withdrawn from the product 19 by means of air motor 27 having a cylinder 28, a piston rod 29 and a piston, not shown. When the tray is withdrawn, the product 19 is dropped vertically upon a support (not shown) which is part of plate 30. This plate and fork arrangement 30 is mounted on a chain which is actuated by a motor unit. Plate and fork arrangement 30 moves the product 19 to the left as indicated by arrow in FIG. 1. Product 19 is inserted into the partially folded container by means of plate and fork arrangement 30. To ensure product remaining in the partially folded container a vertically operated stripping plate, not shown, is raised beneath and between the fork of arrangement 30 thus retaining product 19 in container while plate and fork arrangement 30 are retracted.

The blank slotting and scoring means 31 is provided with a frame 34 which supports a table 32 and movable pivotally mounted stop member 33. Also, feed rolls 35 and 37 are provided to move the half-slotted blank into position and to move the fully slotted blank from the machine. The rolls 35 and 37 are mounted on shafts 36 and 38 to rotate in opposite directions to move the blank 40 from the blank slotting and cutting means 31. As is conventional, the blank slotting and scoring means is provided with a scoring means and a cutting means to form the upper flaps 103 and 104 and slots 101 along with upper horizontal score line 102. The stop member 33 in the scoring and cutting mechanism 31 is moved within the blank slotting and scoring means 31 in response to the height sensing means 20 to accurately position the blank 40 in mechanism 31 so that it is die cut to the exact height of the product 19. After the blank 40 has been formed, the stop 33 pivots downwardly out of the plane of the blank 40 and the feeding wheels 35 and 37 are actuated to move the blank on the table 32 into the position as shown in FIG. 1 and FIG. 4 onto the partial erecting and rotating means 41. As is conventional, a bundle of blanks 39 is positioned to be fed from the lower portion thereof into the blank slotting and scoring means 31.

The machine 1 is provided with a partial erecting and rotating mechanism 41 which is illustrated as being rectangular in form. The partial erecting and rotating means is mounted on hollow trunnions 42 and 43 with the ends closed by plate members 44 and 45. The hollow trunnions rotate about a fixed shaft, not shown, which extends laterally across the erecting and rotating means and is anchored each end outside the operating areas of trunnions 42 and 43. The ends 44 and 45 are connected together by rails 47. Each of the rails 47 is provided with stop lips 46 which are engageable with the blank 40 to retard the advance of the blank 40. Each side of the rectangular partial erecting and rotating mechanism 41 is provided with a container folding means 48 which includes side flap folding means 54, end flap folding means 49 and end wall folding means 50. The side flap folding means 54 is mounted on pivots 55 on the frame structure to rotate the side flap folding means to 45 which in its rotated causes end flap folders 49 to fold about pivots 51 mounted on end wall folding means 50 to fold the end flaps 96 to with respect to the end walls thereof. The end walls folding means 50 is mounted on pivots 52 to fold the end walls 94 to about 87 with respect to the sidewalls 93 (see FIG. 6).

To ensure that the blank 40 is properly maintained on the partial erecting and rotating mechanism 41, a blank holding means 56 is provided which includes a shoe 57 that engages one of the sidewalls 93 to hold the same in proper position. The shoe 57 is mounted on support arms 58 which in turn are supported by a support rod 59. As can be seen in FIG. 4 and FIG. 5, the rod 59 will rotate the blank holding means toward and away from the blank 40.

After the blank has been folded or partially erected as illustrated in FIG. 6, the blank holding means 56 is retracted to position as indicated in FIG. 4. The partial erecting and rotating means 41 is then rotated through 90 to place the container blank with an open side in position to receive product 19 for packaging. To ensure this position of partial erecting and rotating means 41 a pin and stop arrangement is provided with the stop mounted on the sideplate 44 with the pin mechanism mounted from the fixed shaft supporting frame. This position is illustrated in FIG. 7. A sidewall folding arm 60 is provided having a rod member 61 vertically mounted thereon. The arm 60 is pivotally mounted on a pivot 62. As is more clearly seen in FIGS. 2, 3, 7, and 8, the rod 61 engages the sidewall 93 containing the glue flap 97 to fold the same along one of the vertical score lines 98 to completely enclose the product 19. As is illustrated in FIG. 8, sidewall folding arm 60 is pivotally mounted at 62 which is supported by a post 65. A linkage 64 connects the arm 60 with an air motor 66 which includes a cylinder 67 having a piston rod 68 extending out one end thereof with a yoke 69 pivotally connected to the linkage 64. In this manner, the folding arm 60 can be rotated to close the sidewall thereof. When it is desired to adhere the glue flap to the end wall, a glue applicator 63 is actuated to move adjacent the end wall that is adjacent the glue flap 97 and applies a glue line thereon. A vertical pivotal dual rod 70 is provided which is adapted to be rotated about a linkage 71 which is pivotally connected at 72 to a support 73 to fold the glue flap 97 adjacent to the end wall and close the same. This is illustrated in FIGS. 3 and 7.

After the glue flap 97 has been adhered to the end wall, the container containing product 19 will be ejected therefrom by an ejector means 74 which includes a chain 75 extending around sprocket 76 which is mounted on shaft 77. The chain is provided with an abutment 78 to move the container from the position shown in FIG. 1 to the left thereof. The ejector mechanism 74 functions in a reversible manner so that the abutment 78 sidewall partially packed or closed container toward the left as illustrated in FIG. 1 and then reverses itself in response to the rotation of shaft 77.

Adhesive applicators 79 and 80 are provided on each side of the lower portion of the container soas to apply an adhesive on the interior surface of the lower sidewall closure flaps 95. As illustrated in FIG. 7, the adhesive applicators 79 and 80 are mounted on support plates 81 and 82. At the time side panel 93 is folded the support plate 81 with its adhesive applicators is raised to position for application of adhesive on side flap 95. In the upward motion of the support plate 81 a toggle lever is provided to return side flap 95 to a vertical position from its 45 position so said side flap can receive adhesive. After adhesive application support plate 81 with its adhesive applicators is returned to a lowered position to permit passage of product filled container by means of ejector means 74. Accordingly, as the container is moved past the glue applicators by the abutment 78 is response to the rotation of shaft 77, adhesive is applied to the flaps which are subsequently closed.

As illustrated in FIGS. 1, 9, l0, and 11, the bottom sidewall closing flaps 95 are folded adjacent to the bottom end wall closing flaps 96 by spring loaded flap closure means 83. The flap closing means 83 are mounted on each side of the path of travel of the container containing the product so as to close each lower sidewall closing flap. Each of the bottom sidewall closing flaps means 83 are provided with rollers 84 which are mounted on an L-shaped arm 85 which is in turn pivotally mounted on the frame by a pivot pin 86. Accordingly, as the packed container advances toward'the rolls 84, the rolls pivot around the pivot pin 86 and the lateral portion 85 moves undemeath the container to fold the flaps 95 into position as illustrated in FIG. 11. The outer extreme end portions of the members 85 opposite the end mounting the rolls 84 are provided with curved portions 87 to ensure that no inadvertent scoring or detainment of the flaps 95 occurs. This curved portion 87 merely ensures that the container will not hang up in this position.

As the bottom closed container moves past the bottom sidewall closing flap 83, it is received on a receiving ramp 89 provided with arms 90 and 91. The end portion of the arms 90 and 91 are provided with curved portions 90' and 91' to ensure proper sliding movement of the loaded container onto the ramp 89.

When the container reaches the receiving ramp 89, the bottom of the container is completely closed with the top thereof remaining open. The container may then be passed through a conventional top closing machine which can be mounted in line with the ramp 89 to automatically close the top portion thereof.

In operation, it will be assumed that reams of paper are being packaged within the container blanks 40 and that there will be reams per package with 10 reams being divided into two separate stacks with each stack being five reams high. It will further be assumed that the feeding conveyor 2 has positioned a stack of 10 reams of paper adjacent the motor means 16 so as to move the same into the machine. It will further be assumed that a stack 39 of half-slotted blanks 40 are positioned to be fed into the blank slotting and scoring means 31.

Accordingly, the motor 16 is actuated to move the product 19 to be packaged on the conveyor 14 to a position directly underneath the height sensing mechanism 20. Simultaneously with moving the product 19 under the sensing means 20, a half-slotted blank 40 is stripped from underneath the stack 39 and moved to a position engageable with stop 33. Power means are now actuated to move the plate 22 on sensing means 20 down on top of the product 19 to exert a slight pres sure thereon. Accordingly, the height sensing means 20 measures the distance between the upper and lower end of the produce 19. This distance is transmitted by mechanical linkage or other means to the blank slotting and scoring means 31 which moves the stop member 33 that positions the blank 40 properly therein to provide an upper score line, as indicated at 102 FIG. 13, to provide a distance between the score e lines 99 and 102 to the exact height of the product 19 to be packaged. The power means that actuated the sensing means 20 is then reversed to move the plate 22 upwardly and away from the product 19. Simultaneously therewith, the stop 33 is pivoted downwardly and the feed wheels 37 and 35 feed the now regular slotted blank toward the partial erecting and rotating means 41 until the blank engages the stop lips 46.

With the blank 40 positioned on the partial erecting and rotating means 41 as illustrated in FIG. 4, the blank holding means 56 is pivoted down to engage one sidewall thereof with the end walls adjacent the outer edges thereof. This position is shown in FIG. 5. Thereafter, the side flap folding means 54 is actuated and folded to a 45 which in turn actuates the end flap folding means 49 to fold the lower end flaps 96 to 90 with respect to the end walls 94. Thereafter, the end walls 94 are folded along score lines 98 so as to be positioned about 87 with respect to the sidewalls by the end wall folding means 50. Thus the sidewall 93 provided with the glue flap 97 is in the same plane as the end wall 94. With the blank held in this position, power means is actuated to rotate the means 41 to about 87 to position the partially erected blank in a position to receive the product 19 from the side thereof.

With the blank 40 partially erected, the product 19 is therein by actuating the loading mechanism 26 to slide the product 19 into the container. Then the motor means 66 is actuated to move the sidewall folding arm 60 from a position as seen in FIG. 2 to a position adjacent the sidewall thereof to fold the sidewall 93 along score line 98 to completely enclose the product 19 within the container. Thereafter, the glue applicator 63 is actuated to move toward the container which applies the proper amount of adhesive thereto. Thereafter, the dual glue flap closure rods 70 are actuated to fold the glue flap adjacent the end wall as illustrated in FIG. 3 to close the container around the product 19. It is to be understood that the loading means 26 moves toward and away from the open container so that it is out of the position to interfere with the function of the closure rods 70 and 61. Thereafter, the rods 61 and 70 are positioned to return to their original position and the ejector means 74 is actuated so that the abutment means 78 moves the packaged container out of the machine.

As the package is being moved from the position as shown in FIG. 8, the glue applicators 79 and 80 apply a glue line on the lower sidewall closure flaps 95. The package then engages the lower sidewall folding means 83 as illustrated in FIGS. 10 and 11 to fold the lower sidewall closure flaps adjacent the lower end wall closure flaps and adheres the same to close the lower end. The package is then moved onto the ramp 89 for further processing to close the upper end thereof.

While specific details of a preferred embodiment have been set forth above, it will be apparent that many changes and modifications may be made therein without departing from the spirit of the invention it will therefore be understood that what has been described herein is intended to be illustrative only and is not intended to limit the scope of the invention.

We claim:

1. A subcombination comprising: a partial erecting and rotating mechanism comprising a rotatably mounted rectangular frame structure; each side of said rectangular frame structure including a container folding means mounted thereon; said container folding means including end flap folding means for folding the lower end wall closure flaps 90 with respect to the end walls of said container blank; end wall folding means pivotally mounted for folding the end walls about 87 with respect to one of the sidewalls and side flap folding means for folding one of the lower end sidewall closure flaps with respect to one of the sidewalls.

2. A subcombination as set forth in claim 1 together with stop lips mounted on the rectangular frame engageable with the leading edge of said container blank to properly position the same on the frame.

3. The subcombination of claim 1 together with a container blank holding means engageable with one surface of said container blank to hold the same in position while the container is being folded.

4. The subcombination of claim 1 together with stop lip means mounted on a rectangular frame engageable with the leading edge of said container blank to properly align the same on the frame and a container blank holding means engageable with one surface thereof to ensure proper positioning of the container blank during the folding operation.

5. A subcombination comprising bottom sidewall closure flap means including an L-shaped member pivotally mounted on a support base; said L-shaped member being provided with means on the outer end of one leg thereof and positioned in the path of an oncoming container to be engageable therewith; the other leg of said L-shaped member being provided with a curved portion extending downwardly and away from the plane of the L-shaped member engageable with the sidewall end closure flaps of a container blank. 

1. A subcombination comprising: a partial erecting and rotating mechanism comprising a rotatably mounted rectangular frame structure; each side of said rectangular frame structure including a container folding means mounted thereon; said container folding means including end flap folding means for folding the lower end wall closure flaps 90* with respect to the end walls of said container blank; end wall folding means pivotally mounted for folding the end walls about 87* with respect to one of the sidewalls and side flap folding means for folding one of the lower end sidewall closure flaps with respect to one of the sidewalls.
 2. A subcombination as set forth in claim 1 together with stop lips mounted on the rectangular frame engageable with the leading edge of said container blank to properly position the same on the frame.
 3. The subcombination of claim 1 together with a container blank holding means engageable with one surface of said container blank to hold the same in position while the container is being folded.
 4. The subcombination of claim 1 together with stop lip means mounted on a rectangular frame engageable with the leading edge of said container blank to properly align the same on the frame and a container blank holding means engageable with one surface thereof to ensure proper positioning of the container blank during the foldIng operation.
 5. A subcombination comprising bottom sidewall closure flap means including an L-shaped member pivotally mounted on a support base; said L-shaped member being provided with means on the outer end of one leg thereof and positioned in the path of an oncoming container to be engageable therewith; the other leg of said L-shaped member being provided with a curved portion extending downwardly and away from the plane of the L-shaped member engageable with the sidewall end closure flaps of a container blank. 